Gitea: OAuth2 sign-in reactivates an administrator-deactivated account on auth sources without refresh tokens (incomplete fix of #38009)

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

8.1 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

EPSS

• CVE-2026-55987: 0.41% estimated exploitation activity in the next 30 days; percentile 35.57 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Description Gitea's OAuth2 sign-in callback reactivates a deactivated user account (IsActive=false) when the user signs in through an authentication source that does not issue refresh tokens (notably GitHub, and any OIDC/OAuth2 source configured without offlineaccess). PR #38009 added a gate intended to reactivate users only when the OAuth2 auto-sync cron had disabled them, using "the stored refresh token is empty" as the signal. That signal is wrong: for sources that never issue refresh tokens, an empty refresh token is the normal state of every user, so the gate cannot distinguish a cron-disabled account from one an administrator deliberately deactivated. The next time the administrator-deactivated user signs in through the provider, Gitea sets IsActive=true and grants a full session, silently undoing the administrator's action. This is the exact behavior #38009 was written to prevent. (ProhibitLogin, the hard ban, is enforced separately and is not affected.) No special privileges…

Published by the source

21 Jul 2026, 21:02 UTC

Last modified by the source

21 Jul 2026, 21:02 UTC

Source last checked

26 Oct 2026, 15:27 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-vrhc-jjfc-m3m3

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# Patch Next advisory brief: CVE-2026-55987

Advisory: Gitea: OAuth2 sign-in reactivates an administrator-deactivated account on auth sources without refresh tokens (incomplete fix of #38009)
IDs: CVE-2026-55987, GHSA-vrhc-jjfc-m3m3
Record: https://patchnext.com/advisories/cve-2026-55987 (revision 1, source checked 26 Oct 2026, 15:27 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.1)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: code.gitea.io/gitea 1.27.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go code.gitea.io/gitea: affected < 1.27.0; fixed in 1.27.0

## Suggested inspection (read-only)
- Go code.gitea.io/gitea: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on code.gitea.io/gitea.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-vrhc-jjfc-m3m3 (GitHub-reviewed advisory GHSA-vrhc-jjfc-m3m3 lists affected ranges: Go code.gitea.io/gitea >=0 <1.27.0)

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